New anatomical landmark for rotational assessment of total knee arthroplasty

Abstract

One of the most controversial topics in total knee arthroplasty is rotation of the femoral component. The current gold-standard in total knee arthroplasty consists in positioning the femoral component in 3 degrees of external rotation to the epicondylar axis, having as reference the tangent to the posterior condyles. Achieving the correct rotation of the femoral components is one of the main goals during total knee arthroplasty. Multiple complications can result from internal femoral rotation, such as lateral patellar tilt, patellar subluxation or dislocation, mobilization with movement on pain, and low survival rates of the femoral components. Postoperative rotational assessment of protective components can only be performed correctly using computed tomography. The known evaluation methods are related to anteversion of the femoral neck, femoral trans-epicondylar line, insertion of the posterior cruciate ligament from the tibia and tibial tuberosity. The purpose of this study was to evaluate the rotation of the prosthetic components in the group of patients with the methods validated by studies and to find alternatives to evaluate the rotation of the femoral component. Thirty-four patients diagnosted with gonarthrosis, proposed for total knee arthroplasty, were included in the study. This is a prospective cohort study in which applied statistics consisted of analyzing data using frequency and percentage for qualitative and mean variables and standard deviation for quantitative variables